Apparatus for crimping strands



L. TRAPlDO ETAL APPARATUS FOR CRIMPING STRANDS Sept. 24, 1957 2,807,130

4 Sheets-Sheet 1 Filed Nov. 14, 1955 l5 1:: l5 C121 31 l5 1::

CE] ED In: CED [:5 ED U: U: CC] :[3 1:1: [J3 U3 CE! [I]: 1:: EU E: E: III: CE: EU r/h wh vh nah l8 I8 18 I8 INVENTORS y 5 24m g L. TRAPIDO ET AL APPARATUS FOR CRIMPING STRANDS Sept. 24, 1957 Filed Nov. 14, 1955 4 Sheets-Sheet 2 55 mmvroRs 0 4 la 5 BY mi "/5 52!: 51M 9, 5m m Mm 5 A A 2,807,130 1C6 Patented Sept. 24, 1957 2,807,130 APPARATUS FOR CRIMPING STRANDS Leonard Trapido, Kew Gardens, Thomas De Vito, Brooklyn, and Salvator Giarraputo, New Hyde Park, N. Y., assignors to Kahn & Feldman, Inc., New York, N. Y., a corporation of New York Application November 14, 1955, Serial No. 546,310

13 Claims. (Cl. 5777.3)

This invention relates to the treatment of strands made of continuous filaments of synthetic plastic materials, such as nylon, for the purpose of permanently crimping them to make them woolly, springy, bulky, and highly extensible. More particularly, the invention is concerned with a novel apparatus, by the use of which the crimping of continuous filament strands can be carried out at low cost and with a high output rate.

Strands of filaments of synthetic plastic materials typified by nylon have been crimped heretofore by heating them to raise the strand material to its softening temperature and then subjecting the heated lengths of the strands to a false-twisting operation, in which the twist imparted to the strands approaching the point of application of the false twist is set in the strands before they reach that point. Accordingly, when a strand leaving the false-twist device is back-twisted, the twist set in the strand in front of the device is not removed but the twisted filaments are opened up and separated, so that the strand is increased in bulk. Yarns may be made of such strands in various ways, as by combining two of the strands, which have been false-twisted in opposite directions, and the combination of the two strands may be effected by guiding them into contact and winding them as one upon a core or the strands may be plied together with a low plying twist before being wound.

The apparatus of the invention comprises a novel false-twist unit for operating on a plurality of strands and a new false-twist device, which is put out of operation automatically upon breakage of the strand being false-twisted. The device comprises a continuously running spindle and a head driven thereby, the spindle and head being held in operative engagement by the strand being crimped. If the strand breaks, the spindle and head separate and the head stops. Accordingly, a unit containing a number of the devices operating on individual strands can be driven by a single driving means, since, upon breakage of one strand, only the device acting on that strand is put out of operation. The use of a single driving means for such a unit simplifies the apparatus and reduces its cost, but such an arrangement could not be used advantageously, if the breakage of one strand of a group required that all the false-twist devices of the unit be stopped until the break was repaired.

For a better understanding of the invention, reference may be made to the accompanying drawings, in which:

Fig. l is a diagrammatic elevational view of one form of apparatus of the invention;

Fig. 2 is a view in front elevation with parts broken away of one form of the new false-twist unit;

Figs. 3 and 4 are a side elevational view with parts broken away and a plan view, respectively, of the structure shown in Fig. 2;

Fig. 5 is a sectional view on an enlarged scale on the line 5-5 of Fig. 4;

Fig. 6 is a view similar to Fig. 5 but illustrating a modification;

Fig. 7 is a view in rear elevation of a modified mounting for a false-twist unit on the line 77 of Fig. 8; and Figs. 8 and 9 are side elevational and top plan views, respectively, of the device shown in Fig. 7.

In the apparatus of Fig. 1, a plurality of strands 10 made up of continuous filaments of synthetic plastic material, such as nylon, are drawn from individual packages 11 mounted on spindles 12 on a common support 13. The strands pass through guides 14 suitably mounted above the spindles and then through guides 15 on a rail 16 below the support 13 and above tension devices 17 of the double comb type. The strands issuing from the tension devices pass through guides 18 and are then directed by suitable guides, such as those designated 19 and 20, to heating means, illustrated as an electric resistance heater 21. The heater includes a casing 22, which encloses resistance elements provided with leads 23 and has passages for the individual strands formed by tubes 24. In their passage through the heater, the strands are heated to the softening temperature of the plastic material and, in the treatment of nylon, the heater operates at a temperature of 400 F. a

The heated strands issuing from the heater pass through respective false-twist devices 25, which may be of the type shown in Figs. 2-5, inclusive. The false-twist devices are arranged in units in a common support and each device includes a spindle 26, which is mounted for rotation with its axis vertical and is supported at its lower end in the inner race 27 of an anti-friction bearing having a row of balls 28 and an outer race 29. The bearing is disposed in a socket in a plate 30 forming part of a frame 31 with the outer race 29 resting upon the bottom of the socket and the inner race and the lower end of the spindle spaced from the bottom surface. A disc 32, which acts to keep dirt out of the bearing, rests upon the upper end of the inner race 27 and projects outwardly over the bearing to terminate close to the wall of the recess. The spindle has a section of reduced diameter extending through the disc and inner race and rests upon the upper face of the disc on a shoulder at the upper end of the reduced section. The spindle is hollow and the plate 30 has a passage 33 extending from its lower face to the bottom of the recess.

At its upper end, the spindle has a section of reduced diameter providing a shoulder, upon which is seated a disc 34 similar to disc 32 and lying within the lower end of a passage through an upper plate 35 of frame 31. The inner race 36 of an anti-friction bearing encircles the upper end of the spindle and rests upon the disc and the bearing includes a row of balls 37 and an outer race 38 fitting the wall of the passage through plate 35 with a snug fit.

The frame 31 is the common support of a false-twist unit, which includes four spindles and their associated parts. The plates 30 and 35 of the frame are separated by end plates 39 and a plate 40 is secured to rest upon the top of the plate 35 and has openings surrounded by flanges 41, into which the upper end of the spindles project.

A false-twist head 42 is mounted in each spindle and each such head includes a sleeve 43 and a stem 44 mounted in the lower end of the passage through the sleeve and projecting into the upper end of the spindle. At that end, each spindle has an internal flange 26a tapering in diameter in an upward direction and each stem 44 extends through the opening through a flange 26a and has an enlargement 44a having a frusto-conical surface, which is adapted to mate with the tapering internal surface of the flange. A snubbing element, around which the strand is wound in order that the strand maybe twisted, is mounted in sleeve 43 and, in the construction shown, the element is a length of wire 45 mounted in aligned diametrical openings in sleeve 43 and extending across the passage in the sleeve, the wire having a downward bend within the passage. A pair of keyhole slots 46 are formed diametrically in tne wall of the sleevewith the enlarged ends of the slots adjacent the downward bend in the wire.

As shown in Fig. 5, each false-twist head 42 may be raised axially relative to its spindle to bring the tapering surface on the enlargement at the. lower end of stem 44 into driving engagement with the corresponding surface on the internal flange on the spindle. The enlargement on the stem and the internal flange on the spindle thus form the elements of a clutch and, so long as the tapering surfaces are held in contact, the head will be rotated with the spindle when the latter is driven. If the head is allowed to drop, the tapering surface-s on the stem and flange separate and the head comes to rest with a circumferential shoulder 43a thereon resting upon the upper end of the flange 41 aligned with the spindle. When the head is seated on the flange, the lower end of the head is out of contact with the spindle.

The frame 331 is supported on a pair of posts 47 secured to plate 30 and to plates 48 connected by a crossbar 49. The cross-bar is secured to the top of a slide 50, which is mounted for movement along horizontal flanges 51a, 52a of a pair of angle irons, the other flanges 51b, 52b of which lie in contact. The flanges 51b, 52b are secured by a bolt 53 and a clip 54 to a fixed support, which may include a pair of parallel rods 55. The flange 51a has a lengthwise opening 56, through which extends a fixed hollow holder 57 having an internal step hearing at the bottom of its bore and a threaded lower end, upon which is mounted a nut 58. A disc encircling and fixed to the holder lies on top of slide 55 and a spring 60 encircling the holder below the slide bears at one end against nut 53 and, at the other end, against the under surface of the slide within opening 56' A hook 61 secured to the end of the slide is connected by a spring 62 to a hook 63 secured to the end flange 52a of one of the angle irons and the spring tends to hold the slide with the holder at the inner end of the opening 56.

A pulley 64 with upper and lower flanges 64a, 6412 has an axial here, so that it may be telescoped over the holder, and an axial spindle within the bore in the pulley and attached to the upper closed end of the bore is seated on the step bearing in the holder and supports the pulley for rotation. An anti-friction bearing interposed between the spindle of the pulley and the inner wall of the holder limits lateral movement of the spindle. Pulley 64 carries an upper pulley 55 having a top flange 65a and flange 64a serves both as the top flange of pulley 64 and as the bottom flange of pulley 65'. A hook 66 pivoted on disc 59 can be swung to overhang flange 64b and limit the upward movement of pulleys 64, 65 relative to holder 57.

The complete machine includes a plurality of fals twist units, each of which includes four devices 25, and the spindles 26 of the devices of each unit are driven by a belt 67. The belt is trained about pulley 65 and about spindles 26 in such manner that the two outer spindles in the unit are rotated in one direction and the two inner s,-.indles are rotated in the opposite direction. The compound pulley 65 is driven by a drive belt 6%, which bears agai pulley 6d and the corresponding pulleys of the fa wist units along one side of the machine;

Fixed guides 6-9 for the individual strands are mounted on a suitable support above the false-twist devices and the leaving guides 69 are led in pairs through traversing guides 7 The two strands passing through each guide 7%) are wound as one upon a core 71.

in the operation of. apparatus, the strands from the pack s ll are passed through the guides and tensioning devices and their individual tubes in heater 21. The strands are then drawn through the spindles 2-6 of the false-twist devices 25 and the axial bores in the shanks 44 of the heads 42 of the devices and each strand about their respective cores 71.

' are deformed as determined by the twist.

its looped once about the bend in the wire 45 in the head. The strands leaving the device 25 pass through the fixed guide 69 and the strands from two of the devices at one side of each unit may be passed through a single traversing guide 70, while the strands from the other devices of the unit are passed through the other traversing guide. The pairs of strands leaving guide 70 are then wrapped When the machine is operating, the cores are rotated, pulleys 64, 65 are driven by belt 68, and the spindles 26 of the false-twist devices are driven by belt 67.

The take-up of the strands on the cores causes the strands to be drawn through the heater tubes, guides, and tensioning devices and the tension thus applied to the strands is sufficient to cause their false-twist heads to be raised and clutched to their spindles by engagement of the enlargements 44a on the shanks of the heads with the internal flanges 26a on the spindles. The false-twist devices are rotated at a rate of the order of 50,000 R. P. M. and cause the strands to be twisted in opposite directions from their points of engagement with the snubbing elements 45 in their false-twist devices. The false twist imparted to the strands is confined primarily to the length of the strands between guides 2t) and 69, but part of the twist may run backward beyond guides 20 and forward beyond guides 69. As the strands pass through the heating tubes in highly twisted condition, the filaments are raised to the softening temperature and Between the exit ends of the heating tubes and the snubbing elements in the false-twist heads, the temperature of the filaments falls below the softening temperature and the filaments become permanently distorted or set in twisted condition. As the strands pass beyond the snubbing elements, they are twisted in the opposite directions until all the twist imparted to them by the false-twist device has been removed. However, the filaments in the strands retain their deformed or crimped condition and the strands become woolly, bulky, springy, and highly extensible.

Throughout the operation of the apparatus, each strand under tension raises its false-twist head and causes the head to be clutched to its spindle, so long as the strand is unbroken. If the strand, such as that designated 5 in Fig. l, breaks, the false-twist head, which has been operating on that strand, is released and drops down, so that the clutch connecting its head to its spindle is disengaged. The head then comes to rest although its "spindle continues to run. The broken end may then be threaded through the spindle, wound about the snubbing element of the head, and secured again upon the core. As the core applies tension to the strand, the strand raises its false-twist head until the latter is clutched to its spindle and the false-twist operation then proceeds as before.

As a typical example of the operation of the machine, the following data may be given:

The strands had a denier of about and were made of a plurality of nylon filaments of a denier of 1 /2 to 2. The strands were advanced at the rate of about 4 yds. per min. and the heater was maintained at a temperature of about 400 F. The heater tubes employed had a length of about 7" and the false-twist heads were operated at 50,000 R. P. M. The heads of the false-twist devices in the machine had a weight of less than 1 ounce.

The false-twist devices in the form shown in Fig. 6 are similar in many respects to those shown in Fig. 5, but are somewhat easier to thread up and are preferred for that and other reasons. In the construction shown in Fig. 6, each false-twist device 72 includes a spindle 73 supported at its lower end by a snap ring 74 seated in a circumferential channel in the spindle and resting upon the top of a cleaning disc 75. The disc rests upon the inner race 76 of a bearing, which includes a row of balls 77 and an outer race 78. The bearing lies within a cavity in a plate 30' forming part of a frame 31 and the outer race 78 rests upon the bottom of the cavity, while the inner race and the lower end of the spindle are raised slightly above the cavity bottom. The cleaning disc 75 lies within the cavity at the top and overhangs the outer race. At its upper end, the spindle extends through an opening in a plate 35 forming part of the frame and the spindle carries a snap ring 79 engaging and supporting a cleaning disc 80 lying within the opening through plate 35. The disc supports the inner race 81 of a hearing which includes a row of balls 82 and an outer race 83. The frame 31 is provided with a cover plate 40', through which spindle 73 projects, and a ring 84 is mounted on top of plate 40' and surrounds the spindle.

At its upper end above ring 84, the spindle 73 has an external flange 85 of frusto-conical section, which extends into the sleeve 86 of a false-twist head. The sleeve is provided with a snubbing element 87 in the form of a diametrically mounted wire having a central downward bend. The sleeve 86 has a section of reduced diameter at its lower end and the section is adapted to enter ring 84 with the sleeve coming to rest with its shoulder at the upper end of the section 86a resting upon the ring. The inner surface of section 86a is of tapering diameter and the stuface cooperates with flange 85 to form the elements of a clutch, by which head 86 can be connected to its spindle. A guide tube 88 is mounted in an opening through plate 30' and extends upwardly within spindle 73 to terminate flush with the top of spindle 73.

In the operation of the false-twist devices shown in Fig. 6, the strands are led through the guides, tensioning devices, and heater tubes and then through the guide tubes 88 of their false-twist devices. Each strand is then wrapped once about the bend in the wire 87 in the head 86 of its device, which is initially in the same down position as the head 86'. As soon as the strand is placed under tension, it raises its head until the head is clutched to its spindle by the co-action of the mating surfaces on section 86 of the head and flange 85 of the spindle and the head is rotated with the spindle. Whenever a strand breaks, its false-twist head drops and comes to rest on top of ring 84. The operator then rethreads the device and the crimping operation proceeds. The strand may be easily rethreaded through a tube 88 by means of a needle, since the tube is stationary and there is no chance of the strand coming in contact with the continuously rotating spindle.

The false-twist unit shown in Figs. 7-9, inclusive, differs in its frame construction from those previously described. The frame 89 includes a lower bar 90 provided with a pair of integral standards 91 extending upwardly from its front edge at its ends and carrying blocks 92, which extend to the rear and over-lie the bar. Between its ends, the bar 90 is provided with a pair of spaced integral standards 93 which extend upwardly from its rear edge and carry forwardly extending blocks 94 overlying the bar. The false-twist devices 95 of the unit have spindles running in lower bearings in recesses in bar 90 and in upper bearings in recesses in blocks 92 or 93. A front plate 96 is attached to the forward faces of standards 91 and of blocks 93 and can be easily removed to permit a belt 97 to be trained about the spindles of the false-twist devices. The belt is trained about a pulley 98, which corresponds to pulley 65 and is driven in the same manner.

We claim:

1. Apparatus for crimping a strand, which comprises a support for a supply of the strand, means for drawing the strand from the supply, a false-twist device for operating on the strand including a spindle, a head, a snubbing element in the head, and clutch elements on the spindle and head, the spindle and head being open lengthwise to provide a passage for the travel of a strand therethrough, and the head being movable axially of the spindle to engage the clutch elements by the pull of the strand wrapped about the snubbing element, a mounting for the device supporting its spindle for rotation on a substantially vertical axis, and means for rotating the spindle.

2. The apparatus of claim 1, in which the clutch elements on the spindle and head are open lengthwise to permit a strand traveling through said passage to pass through them. V

3. The apparatus of claim 1, in which the head and spindle have telescoping parts carrying the clutch elements.

4. The apparatus of claim 1, in which the clutch elements have mating surfaces, which are surfaces of revolution tapering in diameter with one surface an external surface and the other an internal surface.

5. The apparatus of claim 1, in which the mounting includes a seat for supporting the head with the clutch elements disengaged.

6. The apparatus of claim 1, in which the head encircles the spindle and has a clutch element with an internal surface of tapering diameter, and the spindle has a clutch element with an external surface of tapering diameter lying within the head and engageable with the internal surface on the head upon upward movement of the head along the spindle.

7. The apparatus of claim 6, in which a stationary guide tube for the strand extends through the spindle coaxially therewith.

8. The apparatus of claim 1, in which the head has a hollow shank extending into the spindle and having a circumferential external surface of tapering diameter and the spindle has an internal flange with an internal surface of tapering diameter encircling the shank, the surfaces being engageable to connect the head to'the spindle for rotationin unison therewith upon upward movement of the head relative to the spindle.

9. The apparatus of claim 1, in which the mounting carries a plurality of the devices with their spindles supported for rotation on substantially vertical parallel axes, a pulley is mounted for rotation on an axis parallel to the spindle axis, a belt is trained about the pulley and engages the spindles, and means are provided for driving the pulley.

10. The apparatus of claim 9, in which the pulley is mounted on a support movable toward and away from the spindles, and means are provided for urging the pulley support away from the spindles to keep the belt taut.

11. The apparatus of claim 9, in which the pulley is compound and one part engages a belt driving the pulley.

12. The apparatus of claim 9, in which the belt engages the spindles with its opposite faces to rotate some of the spindles in one direction and the remainder in the other direction.

13. A false-twist device for operating on a strand, which comprises a spindle, a head, a snubbing element in the head, clutch elements on the spindle and head engageable on relative axial movement of the spindle and head to connect the spindle and head for rotation in unison, a mounting for the device supporting its spindle for rotation on a substantially vertical axis, and a seat on the mounting for supporting the head coaxially but out of contact with the spindle, the spindle and head having an axial passage for the strand and the snubbing element having a part within the passage.

References Cited in the file of this patent UNITED STATES PATENTS 2,321,404 McCann June 8, 1943 FOREIGN PATENTS 161,887 Australia Feb. 10, 1954 

